Obesity affects millions of American children and increases their risk of adult obesity, a myriad of serious co- morbid conditions, increased healthcare costs, and premature mortality. Finding methods to reverse this epidemic is crucial. Multidisciplinary behavioral weight management programs offer the promise of effectively treating childhood obesity. However, such programs often suffer from poor adherence to treatment plans and high attrition rates. The proposed project aims to address these problems through frequent contact with patients between office visits. This interim contact will be achieved by automatically sending tailored messages to the mobile phones of adolescents enrolled in a multidisciplinaryweight management program, as an adjunct to clinic visits. The messages will address 6 target behaviors and will be tailored on individual characteristics such as values, intrinsic motivation, and goals. The proposed research project will be accomplished through 4 phases: (1) In conjunctionwith the University of Michigan Center for Health Communication Research, the candidate will build upon preliminarywork to create a library of tailored messages and a computer application to send these messages to participants' mobile phones at varying times of day, receive replies from participants, and to send appropriate, tailored responses; (2) Focus groups with obese adolescents will be conducted to evaluate the relevance and acceptability of the messages developed in phase 1; (3) A four-week trial of the intervention will be performed to assess feasibility and acceptability, and to test the performance of the technology; (4) Apilot test of the 20-week intervention will be conducted among 60 subjects (randomized to intervention and control groups), from the Michigan Pediatric OutpatientWeight Evaluationand Reduction Program, followed by an analysis of outcomes and costs. Career development activities will includetraining in advanced theories and applied techniques related to the design and implementation of behavioral interventions for the clinical setting, advanced data analysis focusing on pathway and cost analyses. Through formaltraining, interaction with her mentoring team, and the execution ofthe proposed project, the Candidatewill acquire the knowledge and skills to be an independent researcher and expert in the field of pediatric obesity treatment. RELEVANCE (See instructions): Obesity is a significant and costly public health concern, yet few effective evidence-based approaches to its treatment exist for adolescents. By using technology to communicate individually relevant information to teens between office visits, the proposed intervention could remarkably enhance obesity treatment and could potentially reach large numbers of teens with minimal incremental costs.